Alaska earthquakes

M4.4 earthquake 77 km S of Unalaska, Alaska

A magnitude 4.4 earthquake struck 77 km S of Unalaska, Alaska on Thu, Oct 28, 2021, 10:28 PM AKDT (06:28 UTC), 10 km (6 mi) below the surface.

Unalaska forecast More in Alaska

Map

Where this earthquake was located, with the others nearby. Select one for its page.

Open the live map with earthquakes

The earthquake

Magnitude: 4.4 (mb), light
Local time: Thu, Oct 28, 2021, 10:28 PM AKDT
UTC: 2021-10-29 06:28:17 UTC
Depth: 10.0 km (6.2 mi), shallow
Epicenter: 53.183° N, 166.701° W
Region: Alaska
Strongest shaking: II, weak shaking
Tsunami flag: No
Status: Reviewed by a seismologist

Shaking

The USGS ShakeMap: shaking estimated from seismic stations and the quake’s size, on the Modified Mercalli intensity scale.

Strongest estimated: II, weak shaking
Peak ground acceleration: 0.2% of gravity
Peak ground velocity: -3.0 cm/s
Map: Automatic

USGS ShakeMap: estimated shaking intensity around the epicenter — Estimated shaking intensity. Map: USGS ShakeMap.

Did you feel it?

No one has reported feeling this quake to the USGS.

How well it is located

Reviewed by a seismologist.

Location uncertainty: About 3.9 km horizontally, 1.9 km in depth
Magnitude uncertainty: ±0.11
Depth from: Operator assigned
Station coverage gap: 136°
Stations used: 126

Nearest places

Distance and direction from each place to the epicenter, with its forecast.

Unalaska, AlaskaPopulation 4,491. Forecast78 kmS

Nearby

Within 100 km, magnitude 1.5 and up: 95 in the 60 days after this one and 45 in the 30 days before it.

After

The first 60 of 95.

Before

Earthquakes today Alaska earthquakes Live radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event us7000fpnl (also filed as ak021dvk1ge5). Read Wed, Sep 23, 2026, 9:04 AM UTC.